The invention relates to a process for eliminating sulfur compounds, in particular hydrogen sulfide from gases containing the same and containing in addition oxygen and/or sulfur dioxide by means of activated carbon adsorption at an elevated temperature between about 120 and 240.degree. C.
In these processes the H.sub.2 S is subject to oxidation on the activated coal and there is thus then obtained elementary sulfur in liquid form at the bottom end of the adsorber.
If the feed gas contains amounts below the stoichiometric amount of oxygen and sulfur dioxide these oxidation agents are subject to complete reaction according to the following equations. EQU 2H.sub.2 S+O.sub.2 .fwdarw.2H.sub.2 O+S.sub.2 I EQU 4H.sub.2 S+2SO.sub.2 .fwdarw.4H.sub.2 O+3S.sub.2 II
The unreacted portion of the hydrogen sulfide is then adsorbed in a second adsorber filled with activated carbon in order to obtain complete desulfurization of the gas.
However, if the gas contains the oxygen in a stoichiometric excess as against the hydrogen sulfide the formed elemental sulfur is further converted to sulfur dioxide. The result is that in the subsequent adsorber more or less substantial amounts of sulfur dioxide must be adsorbed in order to obtain a well-purified gas. It is a serious shortcoming for the economies of the process that usually either hydrogen sulfide or sulfur dioxide remain in the gas which likewise must be adsorbed in the subsequent adsorber and must be subject to further processing.